ARPA-E web chat addresses cellulosic fuels

Since its inception in 2009, the U.S. DOE’s Advanced Research Projects Agency—Energy (DARPA-E) has been actively working to help expedite the development of innovative, game-changing energy technologies. The entity, modeled after the U.S. Department of Defense’s highly successful Defense Advanced Research Projects Agency (DARPA) program, aims to bridge the gap between transformational energy research and industrial innovation.

On June 29, ARPA-E Director Arun Majumdar hosted a live online chat to discuss the investments his organization is making in the nation’s energy future. In addition to a short presentation, Majumdar addressed a wide variety of questions posed by members of the public, addressing everything from the future of the internal combustion engine to the development of a better way to store and transmit electricity.

To open his talk, Majumdar spoke about the future of the U.S., and the role energy plays in its security. “If you look at the future of the United States…that future depends on three securities; our national security, our economic security—or prosperity, and environmental security,” he said. “The common theme in all three securities is innovation in energy technology.”

According to Majumdar, we currently import more than 50 percent of the oil we use. “We are paying about $300 billion a year…right now for that,” he continued. “That is not only an issue for our national security, but this is an economic prosperity issue as well. Imagine if you could spend that $1 billion a day in the United States. That would create a lot more jobs and lead to American prosperity.” Majumdar also stressed that relying exclusively on petroleum-derived fuels for transportation makes our nation vulnerable, from both a national security and economic security point of view.

Majumdar specifically addressed cellulosic biofuels in his presentation. While they offer an important alternative to petroleum-based transportation fuels, he said their production is currently too inefficient and too expensive to replace a significant quantity of transportation fuels. However, he noted that ARPA-E is supporting several products to improve the production of advanced and cellulosic biofuels.

“If you look at the cost reduction opportunity, a lot of it is in the feedstock,” Majumdar said. “How does traditional cellulosic biofuel production happen? You’ve got sunlight, you’ve got feedstock, you need to break down cellulose with enzymes into sugar molecules, which are fed to microbes to produce [fuel]. The expensive part here is the…breakdown of cellulose and collection of feedstock.”

One game-changing method of breaking down cellulose is being developed by a small company called Agrivida, Majumdar continued. “[Agrivida] is trying to put the genes that produce enzymes, called cellulase, inside the plant itself.” The goal is to ensure those genes remain inactive until triggered by a specific mechanism. Once triggered the genes would produce cellulase, effectively breaking down the cellulose of a plant from the inside out. “These enzymes, by the way, are available in cows,” Majumdar said. “That’s why then can eat grass and other plant matter…This is equivalent to putting the cow inside the plant. [It’s] an amazing technology that we have to try, and if this works, it will drastically reduce the cost of biofuel production.”